Promising Results for ZL-1310 in Extensive-Stage Small Cell Lung Cancer

Zai Lab Limited recently unveiled data from its global Phase 1a/1b clinical trial of ZL-1310, a next-generation antibody-drug conjugate (ADC), at the EORTC-NCI-AACR Symposium 2024 in Barcelona, Spain. The study targets patients with extensive-stage Small Cell Lung Cancer (ES-SCLC) who have previously undergone at least one round of platinum-based chemotherapy.

The data presentation, part of the plenary session, focused on the dose-escalation phase of the trial involving ZL-1310 as a standalone treatment. Results were collected from 25 patients across four dose levels (0.8 mg/kg, 1.6 mg/kg, 2.0 mg/kg, and 2.4 mg/kg), with 19 patients having tumors that could be evaluated.

Key findings from this phase revealed an objective response rate (ORR) of 74% among participants, highlighting the potential of ZL-1310 to induce significant anti-tumor responses. The treatment's safety was also found to be favorable, as all patients involved had previously progressed following standard platinum-based chemotherapy, and a majority had also seen no success with immune checkpoint inhibitors. Notably, 56% of the patients had failed at least two prior lines of therapy, and 28% presented with brain metastases at the beginning of the study.

By the data cutoff date of October 10, 2024, 19 patients had undergone at least one tumor assessment post-baseline using RECIST v1.1 criteria. DLL3 expression H-scores were evaluated in 16 of these patients.

Dr. Alex Spira, a medical oncologist at Virginia Cancer Specialists and NEXT Oncology, remarked on the promising nature of these preliminary results, suggesting ZL-1310 could offer a well-tolerated treatment option capable of delivering notable anti-tumor responses in ES-SCLC patients. This is especially significant given the limited treatment options available for this patient group.

Rafael G. Amado, M.D., President and Head of Global Research and Development at Zai Lab, emphasized the company's dedication to advancing novel cancer therapies through innovative research and validated cancer targets. He expressed optimism about the future of ZL-1310, highlighting the company's commitment to advancing this promising treatment through its global oncology pipeline.

Zai Lab is a biopharmaceutical company with operations in China and the United States. It focuses on discovering, developing, and commercializing innovative products to address unmet medical needs in oncology, immunology, neuroscience, and infectious disease. The company's goal is to leverage its expertise and resources to make a significant impact on global health.

ZL-1310 is part of Zai Lab's expanding oncology portfolio and targets the Delta-like ligand 3 (DLL3) antigen, which is overexpressed in many neuroendocrine tumors and is associated with poor clinical outcomes. This ADC combines a humanized anti-DLL3 monoclonal antibody with a novel camptothecin derivative, a topoisomerase 1 inhibitor, utilizing a unique technology platform called TMALIN®. This platform is designed to leverage the tumor microenvironment to mitigate challenges associated with first-generation ADC therapies, such as off-target toxicity.

The ongoing clinical trial for ZL-1310 is assessing its efficacy both as a monotherapy and in combination with atezolizumab, an immune checkpoint inhibitor, for treating extensive-stage SCLC.